Nagano Weather in September
Nagano in September sees high daytime temperatures of 24°C (75°F) and nighttime lows of 15°C (59°F). As part of the rainy season, showers are frequent and often heavy. Budget around 219 mm (8.6 in) of rainfall for the month.
Rainfall in Nagano in September
As part of the rainy season, Nagano sees around 20 days of rain in September, with an average of 219 mm (8.6 in). The rainy season here brings regular, substantial showers. It's worth being prepared for rain on most days you're out.
Temperature in Nagano in September
Expect highs of 24°C (75°F) in Nagano in September, with nights dropping to around 15°C (59°F). During September, you'll experience the summer season. This kind of day-to-night contrast is typical for this time of year. With overnight lows of 15°C (59°F), evenings can feel noticeably cooler than the daytime. An extra layer is a good idea, though the cool air makes for a good night's sleep.
Sunshine in Nagano in September
The area enjoys a balanced 142 hours of sunlight, ensuring it's neither too rainy nor too sunny.Should you favor a climate that's both dry and comfortably warm, May typically offers the most agreeable circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Japan, check out our Nagano's climate page.
Nagano Temperature in September
Min Temperature
15°C (59°F)
Max Temperature
24°C (75°F)
Chance of Rain
65%
Precipitation
219 mm (8.6 in)
Rainy days
20 days
Humidity
74%
Sunshine
142 hours
Percentage Sunshine
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Nagano typically drop from around 28°C (82°F) at the start of September to approximately 22°C (72°F) by the end. Nights are pleasant, with lows typically ranging from 14°C (57°F) to 20°C (68°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Nagano in September
Browse day-by-day weather records for Nagano spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Nagano historical weather extremes in September
The extremes listed below come from historical weather data collected in Nagano from 1976 through 2025.
- The hottest September day on record in Nagano reached 36°C (97°F) (September 1, 2002).
- The lowest daytime temperature in September was 14°C (57°F), recorded on September 27, 1980.
- Nighttime temperatures dropped to 5°C (41°F) on September 23, 2001, marking the coldest September night on record.
- Peak precipitation in September occurred on September 20, 2016, when 76 mm (3 in) of precipitation was measured.
Best Places in Japan in September
Find out more about the weather in Japan and which places have the best travel conditions in this month. See all of Japan in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Nagano in September
Pleasant temperatures in September mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Heavy rain is guaranteed, please bring a good poncho and waterproof everything! Sunglasses could come in handy during the sunnier parts of your trip.What To Do in Nagano in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Japan, check out our Nagano's climate page.
Temperature Rainfall Sunshine Humidity
See the full Nagano climate overview or explore weather in Japan.
